﻿using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int num = int.Parse(textBox1.Text);
            int result = 1;

            for (int i = num; i > 0; i--)
            {
                result = i * result;
            }
            textBox2.Text = Convert.ToString(result);


        }
    }
}
